>=20
> On a one wire bus the so-called "strong pull-up" is only applied very
> briefly prior to communicating with a peripheral.  It is not a resistive
> pull-up as such, since nothing is expected to pull the bus low when it's
> applied.=20
>=20
> Regards
>=20
> Mike
>=20

No, it is applied when one or more parasitically powered 1-wire devices nee=
d to=20
do a lengthy operation which consumes relatively much current (more than th=
e=20
pullup resistor can supply), like temperature measurement, voltage measurem=
ent=20
or writing to eeprom.

There is no need to apply a strong pullup for communication. There is an=20
internal capacitor in each device that supplies power when the bus is low=20
during communication.

It is correct that nothing is expected to pull the bus low during the stron=
g=20
pullup.

/Ruben

=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D
Ruben J=F6nsson
AB Liros Electronic
Box 9124, 200 39 Malm=F6, Sweden
TEL INT +46 40142078
FAX INT +46 40947388
ruben@pp.sbbs.se
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D

--=20
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